I don't have a how-to, but it's pretty easy to make them if you can solder. Here's a list of the parts that I used. I added connectors so I could unplug them, but that's not a necessary step. I had wire laying around so I didn't include that in the list but obviously you'll need that too.
The LED's are adhesive. You just cut them to whatever length you want by cutting them between the solder pads (every 3rd LED).
The lights:
http://www.amazon.com/HitLights-Density-Flexible-Adapter-included/dp/B005ST2I9O/ref=sr_1_20?s=hi&ie=UTF8&qid=1390083450&sr=1-20
The power connector:
http://www.amazon.com/gp/product/B006OQIYFM/ref=oh_details_o04_s00_i01?ie=UTF8&psc=1
12V Power Supply:
http://www.amazon.com/gp/product/B005EK5SNA/ref=oh_details_o02_s00_i00?ie=UTF8&psc=1
Power Switch:
http://www.amazon.com/HitLights-Switch-Female-Barrel-SMD3528/dp/B006U5JWQW/ref=pd_sim_hi_37
Adhesive Cable Tie Mounts:
http://www.amazon.com/gp/product/B00975RMGO/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1
Good luck and if you build them post a picture.