As for kits, mid-west is where I got mine.
I thought this is good info on brewpots if you can get away with a 4 gallon to start.
I found a stainless pot set at Harbor Freight that includes a 1, 2, 3, & 4 gallon pot with lids for about $35 So I mainly use the 4 gallon for boiling. Last night I did two batches where I used the 3 & 4. In the 4 gallon I started an IPA and in the 3 started a wheat beer at the start of the boil of the IPA This way, as I finished the IPA, I transferred the wheat over to the larger pot and it really didn't take me much longer to do 2 beers than it does to do one... This was the first time I did two at a time and i definitely could have used another set of hands...