I make sushi with friends about once a month, and it's not too difficult. The thing that took us the longest to get right was the rice, and we got that down after a few tries. It'll probably take a while to figure out the amount of vinegar you like in it, and how long to leave the seaweed in it while it's cooking.
For nigiri, I've got a little plexiglass box for molding the rice, which makes it somewhat easier to get it a regular shape. It probably wouldn't be too hard to find one, if you're really into making nigiri and don't want to just do it by hand.
We also tried making tamago (sweetened omelet) from scratch last time, and it came out really well. We weren't able to make it the proper thickness and have it cook properly, so we ended up making a bunch of very thin layers, stacking them, then rolling them up and slicing them.
We've started making sunomono as well, which makes a good opening to the meal. Thinly-sliced cucumber, mackerel, and a little bit of miso dressing cut with some mirin (sweetened rice wine). Sometimes we throw a little seaweed salad on top, as well.