I need recommendations for ground cover plants. I need to plant a river bank, so it must be able to withstand blasting summer sun for the majority of the day and grow quickly. The soil isn't that great, although it will be easy to water the plants directly from the river, lol

Rocky, there's no end to the numbers of such groundcovers that will fill your needs.
Many send out runners so that you plant individual plants separately and let them fill in the space.
Some are very invasive...very invasive.
That's alright if you can let the plant go anywhere it wants. It wont go into the river...but it will crowd the banks well.

Goutweed...this one I suggest you not even consider.
Cotoneaster...pronounced co tone aster... a loverly plant this one.
English Ivy
Hall's Honeysuckle
Virginia Wintercreeper
Creeping Potentilla
Periwinkle....this one does well in shade
Euonymus
Lily of the Valley

There's also many vines you might consider and let them crawl on the ground.
Some clematis are noted for that ability

Where there's water...why not think ferns...

Ajuga...bugle flower..this one might get ahead of you if you don't watch it
Wooly yarrow
Lady's Mantle
Crown Vetch...its a tall one...growing up 24" +
Snow in Summer
Sweet Woodruff
Dead Nettle...its not dead..
Japanese Spurge...pachysandra
Ground Phlox
Scotch Moss
Dragon's Blood.....pretty when you can get it going
Thyme
.....the list goes on.....

Rocky, check out this link. You'll find info and pictures which should be of great help!

http://springhillnursery.com/category.asp_Q_c_E_2

hayland, thanks for the suggestions, I'll look those up on the internet.

broofrumom, thanks for the link, I'll take a look.