Monitor brightness can be adjusted pretty easy. Just adjust your contrast & brightness until you can see each section from white to black:
If you've just changed from analog, it might take awhile to get it adjusted, and your eyes adjusted to it. There's lots of little tweaks which should be done. First thing I'd suggest (thanks to Barri Olson (madlights) for pointing it out to me) is going to the manufacturers site to check for updates. If I recall, the driver needed updating for my Dell straight from the box. Next step is setting the color profile in Photoshop. Read the directions which came with it, and if it's not clear, Google will be your best friend.
Color correction is a separate matter all it's own. But even without spending $250. for a spyder, you can still get it close enough. One of the primary problems is color being influenced by the browser you use. It might look perfect in Photoshop, then vary online. I can't recall if it was Doug, Dave or someone else (sorry, but jump into the thread, please) who brought this to attention sometime back, including the link to this article explaining the differences. Well worth the read:
http://www.gballard.net/psd/go_live_page_profile/embeddedJPEGprofiles.html#While it sounds confusing, it's really not difficult, just takes a little reading and you'll figure it out. If I can, anyone can!
Now if I weren't so lazy, I'd correct the photos I posted when using my uncalibrated analog.