KEEPING TRACK OF BLOGS

How do you keep track of blogs?  I like to follow them along for a while before I list them on my own blog as blogs I follow, and I've been doing that with Google Reader. And I find this works well for me as I can see at a glance if there's any new posts.  Fine - except that every now and then Google Reader decides to delete them all.  It did this AGAIN on the week end, and I spent ages trying to remember which blogs I've been following so I could put them back again.  But today guess what - they all appeared again.  Has Google Reader done this to you too or am I just missing something.  I could well be the problem.  Some computer stuff  just eludes me completely.