For ease and simplicity, may I suggest you use 2, 3, or 4 watt CFL's (I recommend Microbrites) and use them in as small a can as you can find at your local home store or electrical supply house.
A coworker of mine did this after great consultation with me describing exactly what he wanted. He has like 14 3 watt CFLs on a timer he got from Home Depot awhile back that changes time along with the suns rising and falling with the seasons to they come on exactly at the right time.
Yes, you could easily make your own heatsinks, glue LED's on and power them with a commercial LED driver or drivers. However, the CFL's are just to easy to use for now to screw with all the LED stuff. Believe me, after you have drilled the holes in the eaves, ran wire all around the house up there, you will just want it over and screw in some bulbs and be done with it.
Bob E.