This past year i've gone from a 24 to currently a 14/16 (and still shrinking), I really understand not having any clothes that fit properly. When I'm in between sizes, I just dealt with the ill fit, knowing that in a few weeks I'll be a different size anyways so it doesn't make sense to buy new clothes.
Thankfully I kept some of my 'skinnier' clothes so until recently I always had clothes to wear. Of course, now those skinny clothes are a full size (or more) too big. And I'm also stuck with having to buy new clothes. Since I plan on losing another 60-70 lbs, it seems wasteful to buy a whole new temporary wardrobe (plus I can't really afford to spend that much money).
I've been shopping thrift stores with mixed results trying to get some basics that fit (jeans, black dress pants, khakis...). Also, if you don't mind buying online, I'd highly suggest ebay. A few weeks ago I bought a mixed lot of clothes sized 12-16 for $125 (including shipping), it had 35 pieces (tons of tops/bottoms and a few accessories) and all was gently worn, and better quality than I found in my local thrift stores. Finally, if you don't want to spend too much money you can always try outlet stores, places like tj maxx, ...
Good luck!
