I'm Jorge, Portuguese, but presently living in Italy. I would like to develop my analogic photo skills. I have 3 cameras, an Olympus OM-10, a Vivitar XV2 and a toy camera Diana mini. I have just discovered this forum and I hope I will learn a lot. I use this opportunity to ask your advice for some good begginers book (somebody told me the 35 mm handbook, but i can't find it) and also with which camera you think I shall use.
Welcome Jorge! The choice of camera is very personal- and also depends a lot on what presents itself. I use Canon FD equipment because I got it for very little money, and I love it- but there will be fans of every major brand out there, so look around for what is available and cheap if you're looking to get another camera. You have a great start right now with what you have. As M.A.Longmore says - use them all!
I second the suggestion of Hedgecoe's The Photographer's Handbook. It is what we use in the photo classes at my school.
Welocme Jorge to APUG! Most of my cameras were 'hand me downs'. The cameras you have are perfectly fine. You might go to a library and lookup some books.