You could always get them to setup a gift register at a baby shop (baby bunting etc), they basically buy off a list you pick (fun for you to go looking aswell) OR they put money in and it all goes onto an account for you, then you get to go in and pick whatever you want.

The other option is some people do vouchers for nappies etc, if your going cloth there are services that you can get vouchers for they come and pick-up dirty nappies etc and wash them for you.

I didn't have a baby shower but my friend made up a basket and every time she went shopping she got something little to put in it, baby bath, wipes, ear cleaners, face washers, small bath toys things like that.

Have fun... i'm sure it will be great