What do i use to pump up my nitrogen shock?

Do a search on the subject, it has ben discussed at length. However, in summary, the key in clean and dry. You cannot get this out of a normal pump or compressor setup. Nitrogen fills the bill nicely and is relatively cheap. If you need your shock recharged, just take it down to your local shop.

Most shops only charg you $10 or so dollars to just fill it with nitrogen.