If they are normal non-smart strips - 4 wires, 1 for each color and a common - then the simplest way is to use one of the cheap $7 dmx modules out on the market. They have a 2 wire data in cable, 2 wire power in cable and a 4 wire output cable. Designed for 12v dc. The one I have here can do 2A per circuit/color on rgb strips/modules/nodes. There are also some cheap 45w power supplies out there also i think for $14 each.
I would send you to David Moore's site, but something is wrong with it - looks like the domain expired...
Myk