How big is my niche

[zoeinthecity]

I have an idea (yay me!)

How do i find out how many people search for a certain phrase each day? i've found the "top 500" lists and all that... but i want to know how many people search for my particular thing each day.

Is there a website that i can try? or do i need to log in to adwords ?

[webgal]

http://tools.seobook.com/keyword-tools/seobook/

You can use this. It's a little overwhelming at first so be patient while you learn what it does.