When starting I think its best to checkout many catalogues so you can decide what product line is best for your market. If you can attend the ISS Show in Atlantic City in March you can collect (or have them sent) lots of catalogues
http://www.issshows.com/ while having a chance to see and touch garments.
There are Reader's Service cards in at least some of the free industry magazines (Stitches, Impressions) where you can request catalogues.
In addition to choosing a supplier who offers the type of items that sell to your market, choose a supplier with a free freight policy and who can cater to most of your needs. If you order primarily from one vendor you'll save shipping cost and time while building buying power with that vendor. If you offer items from a range of suppliers or go on a vendor hunt everytime a customer requests a small order of something your usual vendor doesn't offer then you'll waste time and money.
Also be aware of sales and ask to be added to email lists of sale items especially if you purchase lots of T's and sweatshirts.
I use SanMar as a primary vendor although I occasionally purchase from Bodek & Rhodes, NES and and ACC. Atlantic Coast Cotton (ACC) is a good vendor to check out because they have a wide offering. The are located in VA (one day ship to me in NJ). Although not on the east coast, you may want to check out S&S
www.ssactivewear.com because they supply a wide range of trendier items along with the basics.
When choosing a vendor, request trial case pricing. Many vendors will put you on temporary case pricing and keep you there if you do a certain volume with them. Also, some vendors have case pricing if you order online so keep that in mind when ordering.
Help gathering suppliers / distributors list
