Internet drop outs?

[Socket eh?]

I'm on dial up because I live to far outside the city to have access to anything else. I don't mind it, but I've been getting a lot of drop outs lately and they can be costly sometimes. It happens randomly, where I'll stop receiving packets at all and my modem continues to try to get the connection back, or so I think. Sometimes it doesn't happen for a day, other times it happens every 2-3 minutes and can be VERY annoying.

How can I figure out if it's at my end or the ISP's? And does anyone have any ideas? Modem settings, etc.