Post a pic.
Could be any number of things.

Josh

If you can't post pix, could you at least try to describe the plant. Sorry, but w/ neither a pic or a description (or the slightest clue what kind of plant it is) it's simply impossible to help you.

DLT78, the easiest way to identify your plant is to go to a local nursery, look for it there and ask one of the employees to tell you its name.
Then tell us whether the affected leaves are the young leaves near the top, or the lower mature leaves, or all leaves.
A leaf changes color in a particular pattern depending on the cause. Generally it goes from light green to yellow to brown. So where does the yellowing start? From the tip working back along the margins only? Or from the tip backward across the whole leaf?
Does the affected portion stay firm, eventually turning crisp or does it go limp, soft, slimy?
Do you see narrow bands of brown near the tips or are the leaf veins more green or more yellow than the rest of the leaf tissue?
And while you are looking closely at this plant to answer all these questions, check to see if there are spots or specks of any color on the discolored AND the healthy green leaves. Check for sticky secretions. Give the underside of the leaves (or where the leaves cluster around the stem) a light misting spray and look to see if a web appears. This will indicate sucking insects that consume the juices from the leaves and the plant will look as if it needs water.
Before you post (and please do post), poke a pencil or thin wooden dowel all the way down to the bottom of the container; leave it there for about ten minutes and when you pull it out, try to determine how many inches of the rod is wet.
Finally, welcome to the forum. What you have been asked to do is what many of us here have had to do for hundreds of times. I can guarantee you that it will get easier, effortless and fun.

Well I want to see it, too. Some of the free photo-hosting/sharing sites people use are imageshack, photobucket, flickr. Each is slightly different in how they work. If you do a search for these sites, you should find a myriad of options. The 3 I mentioned are known to work well showing and linking pictures in these these forums.

If you don't want to get into that, it's not really necessary to identify your plant to increase your knowledge and know what to do for *most* house plants. This discussion probably has more than enough info to get your plant back on the road to being healthy.