Finding the cheapest cell phone provider or credit card isn’t easy. You can spend days pouring over paperwork, trying to figure out what fees actually mean. But BillShrink makes all of that easier.

BillShrink will go out and find you the best credit card for your purposes. By answering a few questions about your typical spending habits — such as where you shop the most often — BillShrink will find the card that maximizes rewards, minimizes fees and generally meets your needs. The site can help you narrow down your search by limiting rewards and other factors: if you know that you want to save up points for a vacation some time soon, maybe you specifically want a card that will get you miles you can trade for plane tickets.

This site can do the same thing with your cell phone bill. You have the option of allowing BillShrink to access your actual bill by providing your cell phone number and password. If you’re uncomfortable with that option, you can also estimate your bill. From there, you can answer a few questions about how often you use your phone, where and details like text messaging and the number of lines. If you have a particular phone that you simply have to have (like a Blackberry to handle work calls), you can actually set the phone type as a search limit.

So far, BillShrink only offers comparison services for credit cards and cell phones, although it looks likely that they’ll expand to other services in the future. I’ve got my fingers crossed that they’ll check out internet service providers next. In the meanwhile, BillShrink is a pretty useful tool. It provides an easy way to compare credit cards — one of the most difficult categories of bills simply because of the thousands of options available.

You can even set up a standing request with the BillShrink website to be notified anytime a better credit card offer becomes available — the same goes for cell phone plans. Simply submit your email address along with your search criteria, and the site will automatically email you if it finds a better deal.

There are a number of personal finance tools available on the web these days, and most take a broader view than BillShrink. But that narrow focus makes BillShrink particularly useful. Don’t expect to spend days, or even hours, on BillShrink. Instead, you’ll spend only a few minutes getting results on BillShrink, even if you take the time to set up notifications. You might spend a little longer changing your credit card account, but that’s about it. Using BillShrink is a simple step you can take this afternoon and not have to worry about for a while. Consider taking five minutes sometime today and see if you’re really getting the best deal on your cell phone and credit card.