Macro to search spreadsheet

Hello

I'm looking to make a spreadsheet at work to help myself out.....I'll try and make this as clear as I can! Firstly, I'm using excel 2003....

On the spreadsheet, I currently have a list of about 300 lines which are names of schools. What I'd like to do is create a command button with a macro behind it where I can put a school name in a text box, and the macro checks to see if the school is on my list or not

Is that possible? I did macros on excel briefly in school years ago but can't really remember much about it.

Thanks to anyone that takes the time to help

David.