awwww #@$! help me out plz

ph can move either because it hadn't stablized from when you filled the tank, or it could be something in the tank ie rocks, shells etc that are affecting it.

Agreed, most likely it hadn't stabilized, however there are other things you should consider. Ph is something fish can adjust to and although 7.1 to 8.0 is a big swing guppies are generally pretty adaptable fish.
Next thing is that being new fish it is possible they just weren't healthy, or the stress of moving did them in. I highly reccomend the fishless cycle method, but either way I wouldn't get too discouraged, IMO most fish that die within a week of bringing them home were bound to die anyhow. with ammonia and nitrite never going up, it probably wasn't your fault.
If you re-attempt fishy cycling, acclimate any new fish slowly, by adding small doses of your tank water to their bag every 30 minutes or so until there is more tank water than lfs water in the bag. This will acclimate them to ph a little better, and once acclimated they will do fine in 8.0. if your tap water doesn't test that high after sitting out in a shallow bowl over night then look for anything in your tank that might be contributing, somthing is melting/leaching into the water.

I agree with dave. Its seems way to early for it to be anything you've done. I would also recamend the fishless cycle. Lately it seems guppies just aren't very hardy fish anymore... Maybe try a different fish to cycle. Of all the ones I"ve gotten lately about 50% die. The ones that make it are extremely hardy, and obviously the ones that die... well aren't.

For the price though, why not go fishless? How much is a small bottle of ammonia? A couple bucks? Why spend money on fish you may or may not want? Get your fishless cycle going and while you're staring into the empty tank, going crazy, wondering "why oh why aren't nitrites dropping?", you can think about what you'd like to do with the tank. Peruse the web, check out some different types of plants and fish at your lfs and online. Then, if there's any other hardware, decorations, toys you decide you need you can work that into the plan without the hassle of worrying about fish.