The first thing I got is the Dritz Ball Point Bodkin. (I linked to Amazon for reference but it is actually cheaper to buy at JoAnn's, especially if you have a coupon.) It is a long ball tipped needle with a hole large enough to thread elastic through. I was able to put the elastic in my latest pair of baby pants in about 10 seconds! Never have to use a safety pin again! If you find you are always fighting elastic through a little skinny casing, you should definitely get one of these.
I also discovered the Dritz Magnetic Seam Guide. Again, it is cheaper to go to Jo-Anns and buy, especially with a coupon. It attaches right to the plate on your sewing machine. You just place it at the appropriate distance from your needle and then feed the edge of your fabric against the edge of the seam guide. It is that simple and I have come out with perfectly even seams on everything!
Hope this is helpful to someone!