paris

Arround the Gare de Lyon there are many chep hotels as well as in Gare du Nord

Re beach - have you tried to look at a map :-) ?
At google earth you can actually SEE the beaches (the sand)

For good cheap hostels I'd suggest the AIJ (right near the Ledru Rollin metro in Bastille) - http://www.aijparis.com/<BR><BR>It's really cheap, clean and secure, and is a great base for seeing the sights by foot / metro. The only drawback is that you can't book online, instead you have to email / fax them your credit card number before they secure you a room. On the plus side the rooms host four people max, and while it's no palace, you certainly get what you pay for.

The BVJ hostels (in the Latin Quarter and Louvre) are also central and secure (you can't book super in advance though for some reason)

:-)

I stayed at Peace and Love Hostel, and it was ok. The showers in the room had no curtains, which I found incredibly odd. The people were nice for the most part. There was a bar downstairs, if that interests you.

you might find http://www.parismapped.com of some use. it is a searchable interactive street map of Paris. Hope this helps