Before posting this, I did RESEARCH and took a yoga/gong meditation class. Perhaps tequila shots could have been a substitute for the latter...
OK! You've pretty much decided what you need, and you can't properly do this alone WHAT are your options?
Get referrals - hopefully based on experience. If you are looking for a single product type (shades or some other non-drapery window covering) or a couple of things, a well-experienced/educated sales person can be where you start. Look around the store/showroom and watch and listen for someone knowledgeable. It's possible that the store will have a sequence for matching up salespeople with customers, and someone will jump as soon as you come in.
Carpet, flooring, tile, lighting, kitchens/baths all fall in this kind of category. Some of the best experts I work "in the trade" with do retail sales as well and have abundant information to share.
Not enough? But know where you think you'd like to shop? Many furniture and some department stores have "decorators" or "designers", at all levels of taste and expertise. They likely have different training/design education backgrounds than independent designers. But they will know their products. Retail is retail, and they are primarily salespeople. If they are having a 30-40% off sale, go for it. If it includes delivery, prices are good. Can be Very Good. Again, they will (and should) mostly sell what they show: Walter E. Smithe & Ethan Allen, Crate & Barrel, Pottery Barn & Bloomingdales are in that category. Some retailers might offer no-interest financing these days. If you can get it, that's an awesome opportunity.
OR, is this a multi-faceted project? Do you want access to all the showrooms and all the bells and whistles? Many specialized retail showrooms also discount to "the trade". Then you should consider a design professional for your home, or office or whatever your interiors project.
In order to get into the "real" wholesale showrooms or get "trade discounts" all most vendors require is a resale (sales tax) number and a business card. Many showrooms don't think that's enough. Doing a beautiful job decorating your own home or your neighbors' condo is not enough experience and knowledge to be a design professional. A Designer should be able to understand Construction Documents (blueprints and specifications) and even help you make some educated changes, do all you expect and later introduce you to art, antiques and accessories.
Illinois REGISTERS Interior Designers. One who is qualified by the State (& has that 5 x 7 bluish Certificate somewhere, with a number on it, like a barber or a doctor) is considered a Registered Interior Designer. That is not the same as a Decorator or a Designer. If y'all ask, I'll explain more, but there is an "act" (yep, "legalese") published on the State of IL web site that explains ALL of it. If you fit the education criteria and have passed a Qualifying Exam, you can be registered in Illinois. The web site lets you look people up.
The same criteria as required by the state qualify a designer to be a PROFESSIONAL member of ASID or IIDA, the predominant Interior Design professional organizations in this area. The membership commitments are substantial, so they attract serious folks. Other organizations include IDS -- residential, and CID (which is Decorating). AAHID is an organization for Health Care facility designers.
Education and work, but no multi-section national qualification exam (NCIDQ), in ASID makes you "Allied". "Allied" was originally set up as a pathway to Professional membership and to be held for a limited time. IIDA non-Professional Designers are Associates. Some architects do interiors. I would never speculate on their ability, but there are thousands of sources around, and it's not easy to understand products you don't work with ALL the time.
By the way: LEED (Leadership in Energy and Environmental Design) designation means that the person has been qualified and tested in Green Design. LEED AP is the Professional title, broken into divisions based upon the type of projects. GA (Green Associate) is for more basic knowledge in Green Design -- I have taken the prep course and hope to take that exam, perhaps in the fall.
First: personal referrals. From work, your family, your architect, the gym, the showroom salesperson, a contractor.....check credentials, experience in the kind of job you need. If you get a name from someone, use these tools. It seems that most Designers have a web site, Facebook Fan page, Twitter account, or a combo.
ASID and IIDA have offices in the Mart. On their web sites, searches connect to names of Designers. ASID lists Prof. and Allied members, some link to individual web sites.
You can Google: Designers, IL Designers, IIDA, ASID etc, and it will work, but muddling through will be cumbersome (I just tested it) and remember that the ones on the top and in the side columns pay for those ads. Good for them! Really! But it doesn't make them more qualified, just more visible. (Like this Blog is for me!)
Then call! and between your questions and theirs you'll both know if you want to pursue the conversation in person. Ask how and what they charge. Probably, you'll get a different response from everyone. Unfortunately for the consumer, there's no one method. Years ago everyone charged based on List (or suggested Retail). Now, it's everything from a Tiered Set Fee (depending on the complexity, size of your project) to full List, plus freight and delivery (don't forget that component) or by the hour. Combinations are OK, too.
Mull this all over for a few months, and then we can get back to the easy more specific subjects (just kidding), but this IS heavy lifting). This information belongs "out there". Now I can start reading "The Practical Encyclopedia of Feng Shui"