okay so the stock 15's (wheels and tires)are sitting in the garage corner gathering dust and im wondering..' Should i do something to these? Is there some (if any) sort of prefered preservation method?

I don't plan to switch back anytime soon but on the same note throwing them on ebay for 100 bucks seems like a waste as well. so i wann a keep them "just in case"

Any tips or suggestions?

How cold is your garage? Best place to store the tires is in a basement is possible. Check tire pressure before you put them on a car though. Remove anything that could cause oxidation to the steelies.

well its las vegas so sorta cold in the winter (40 or less)and mad hot(95+) in the summer.

should pressure be high or low?

EDIT:
Finally found this long lost PDF file from Yokahama:

http://www.yokohamatire.com/pdf/tsb-112102.pdf

Info from 1010tires,(bolded by me):
"Tire Storage

Storing Winter Tires
The best place to store winter tires is in a cool, dry location. (Basement, or possibly a garage). You can lay them down flat, stacked on top of each other no taller than 4 high. This offers the most support and should eliminate any fitting problems the following fall. We also recommend that you return to the store/dealer from where you purchased your tires from and ask for storage bags. This will protect the tires from natural ozone in the air which can cause tire rubber to dry and crack. Wrap each tire individually and stack them. Stored tires should be kept away from electric motors or welders as these produce ozone which will damage the rubber over time."

I believe I read this in those "technical question" section of Road & Track....

If you drive on the tires occasionally they will be less prone to cracking. Driving works the natural lubricants that exist in the tire rubber around so that the tires won't dry out and crack as fast.

EDIT:
Finally found this long lost PDF file from Yokahama:

http://www.yokohamatire.com/pdf/tsb-112102.pdf

EXCELLENT! thanks fr130 thanks the perfect information. time to go deflate some tires. :D