Database

hi
i trying to create a portal like e-bay.com,where in i have to take the
data from the user(like-country, category) and all . how can i do that
in ruby on rails and i want the guidance for the model of database etc.
Thank you

Try these books:

http://www.pragmaticprogrammer.com/title/rails/
http://www.apress.com/book/bookDisplay.html?bID=10178