Belkin makes an ADC to DVI adapter (which I use, and works fine) that goes for around $30, and Griffin makes a nice-looking ADC to VGA adapter that costs about the same, maybe $5 less. Dr. Bott also has an ADC to VGA adapter, though I think it's not as attractive as the Griffin one (which I own).
If you shop around, you can probably find either for $3 or $4 cheaper, but watch out for shipping and tax.