Watch Nashbar ads. They've sold Raceface 130mm bcd 53T-39T chainring sets for $7.49 several times this year. These are index chainrings with pins and ramps. Regular price is about $20 a set. These are nice because they include the chainring bolts and nuts. Most all other companies sell the bolts and nuts separately.

Even if you end up paying full price because you can't wait for a sale, they are not a bad value. Shimano gets more than $20 for a single chainring.

When they go on sale, someone usually posts a message to make other people aware of the sale.