General : Too many email addresses

I have email accounts with Google, Yahoo, Hushmail and my current ISP, but I can't seem to reduce the number of them. I like to use my Yahoo account to register for sites that I am sure are going to spam my mailbox, I use my Google Mail account to invite friends and when some sites cannot take the length of my ISP address, trust me, its a long email address then my ISP addressing acts as my main email account for companies I trust, ie; Amazon, Play and a few select others, but that is where the problem lies, like most people, I want a good deal on my broadband, so I change my supplier on a yearly basis, I then spend weeks updating my favourite suppliers with my new address, or reviewing my old ISP mailboxes until they are disabled. I would like to use Google Mail, but it a free service, littered with adverts based on my personnel email and what if Google change their policy and decide to charge? Is just me or does anybody else suffer from this?