Hi,

There are many options but this is where I got my starters and food. (You will get a lot of opinions on what food to use. Just want to let you know that the food at this site was loved by all the roaches! )
http://www.blapticadubia.com/

If you are not going to use any for feeding right away then just go with adults. One male for every three females is a good ratio but you can go with even more females if you want. I cannot remember what their life span is but you should not have any die off for a few months.

As you have already found out, they are easy to keep and multiply quickly. The biggest key is to keep them warm. High 80's worked for me. I started with a mix of 50 and had over 1000 in about 4-5 months. (I never kept track of the actual time frame but I know it was not long at all.)

Remember only the males have wings and rarely fly . . .

Good luck

Jim