It's something you really want to learn to fit yourself, i know it's a bit daunting at first and a bit fiddly but once you've done it a couple of times then you'll really get the knack of it.
I buy my tyres separately then take the loose wheel to be fitted which not only works out cheaper for me, but it means you get to clean and grease the spindle, fully grease where the sensor goes, plus it avoids the small possibility of someone else snapping the lugs for you accidentally. It's rare but not unheard of.