Help. My Mac is losing its space.

My mac started out with 250 gb. When I added programs it then was reduced to 239 gb. I would then add 15 gigs worth of media. Then I saw something strange. I Had 178 gb two days ago, then 177 yesterday, and today I have 176.
So how can I fix this, how can I get that lost memory back?

you can get your hard drive space back by delete files and/or programs.

as you install programs and download files, the space will become smaller.

backup files you don't use much to cd or dvd, or an external drive... then you can remove them from your main hard drive to gain that space back.

try searching through every application you have and see if it downloads/saves files automatically. for example, on one of my AIM clients Adium, it saves all chat logs I have automatically. so, over time, my hard drive spare does go down! try checking things like that...good luck!