Jeanie I have been buying my DMSA from this site. It is pretty cheap considering what the compounding pharmacist was charging me! This site charges $29 a bottle of 120 capsules. They are the manufacturer of the DMSA.
http://www.vrp.com/ProductPage.aspx?ProdID=8112
I ordered 2 bottles and they ship very quickly. I ordered it on a Wednesday and had it that Saturday.

I found another site that is cheaper. This site charges $26 a bottle of 120 capsules. They have a further discount if you buy 3 or more bottles. I haven't ordered from them yet, so I can't really say how good their customer service is. Rather than buying directly from the manufacturer (VRP), you can buy from this place. You'll have to scroll down the page to find the DMSA.
http://www.vivagen.net/detoxprods.htm

As long as you go slow, Jeanie you won't regret it. There are a few people on here who are going WAY WAY too fast and they are suffering from it. It's not hard to see who is taking too much DMSA and/or ALA. This doesn't have to be you. Just remember what is a small dose for one person isn't necessarily a small dose for you! My husband and I certainly learned that this past week. Everyone's body is different.

I hope your other troubles work out. I will keep you in my thoughts.