i m devloping an online auction system and has to be devloped in OO, there are few classes like
Users(not registered)
Members(registered users)
AuctionSystem(handling operation regarding auction and other stuff like closing auction etc )

the problems i m facing are:
1) Registeration method: should it be a part of users, as they can register themselves or it should be aprt of AuctionSystem as this system should add user to the db, one more thing there is going to be a mail generated to the user having complete reg info like name pass etc.
or do i have to pass info prom regis page to user and then to AuctionSystem...

2)should login be a part of Members methos, i m confusing it like, if member is not successfully logon then how can we create an object before and accessing its method??

3) there are 3 tables one for items, second for auction and third for bids, wat abt objects, as i m very new in this oo domain i don't know which classes i should develop, do i need to develop only one class of Auction or wat?