Login

I am producing a site at the moment to produce and sale framed prints for artists.

I need to provide a login area where they can check their sales.

I use a photo library site where I submit images and I can login to check my sales and also see how many 'zooms' I have had on my images, which would be perfect. Is this difficult to do?

I would prefer a readymade add on as I am not that familiar with html coding and something not too expensive, maybe even freeware?

Thanks.