If it isn't already too late...
How are you planning on cooking, saucing and serving the salmon?
Will you be cooking it med-rare, med, or med-well?
Assuming you're going with something relatively simple, and not overcooked....
Chef Layne made several very good suggestions. Asparagus is magic with many, simpler salmon preparations; you can serve them on the same plate, so they can both be enhanced by the same lemony sauce.
In terms of vegetables, things which shout spring (like asparagus) and summer are your best bets.
As to starch, there are not only a million choices; many of them lend themselves to myriad variations. You might try adding to your rice repertoire with a herbed mix of brown and wild rices (okay so wild rice isn't really rice). Both simply herbed bulgur and couscous would give you the right amount of taste to complement salmon -- which is fairly assertive -- without overwhelming it; and supply some texture. New potatoes in parsley and butter would be very good with most salmon preps; and can you ever go wrong with sauteed potatoes?
BDL