Since you've likely never been close to the weight you are now, you probably have next to nothing to wear. So I say go out and get a few things. While you may need help dressing your new figure, I'd rely on a friend with style rather than the sales person, because with transitioning weight, you will want to shop discount, TJmax, Marshals, Nordstrom rack.
I only gained 30, but am always so desperate for new clothes after each baby. Stretchy fabrics and things that tie at the waist, give some room to shrink and still continue wearing the garment.
Consider investing in a great pair of black stretch pants (or just leggings, but a thicker pair is a little dressier) that you can wear under larger shirts and a pair of boots. I invested in a nice pair at Talbots, but will take it in if I have to. I got great use out of it in winter, but no so much in warmer temps. In WA, I think you could make use of that look nearly year round.
Also, consider investing in really nice shoes. It will really help your outfit and your feet will stay the same size!
I'm used to spending $150 on a nice pair of jeans. But I picked up a totally decent pair at the Gap and paid half or less than that.
Little jackets and cammies cover that stubborn tummy
lots of long tank tops that you by in a three pack at Costco cover your tummy under shirts that and showing too much and give a nice layered look. (great of nursing too)
If you are loosing weight steadily, buy one or two things to get you buy till the next size. If you are plateauing and know you really need to work at loosing the weight, then buy a few things now at discount, and reward yourself with every new size with a few more discount items. Just enough to get by. Don't worry about wearing the same thing over and over. Its a temporary situation.