You can save a lot of money on your prescription drug bills by tracking down lower-cost alternatives and finding the cheapest pharmacy. But most people have absolutely no idea how to shop for prescription drugs - or how much they can save by learning about their options.

Several great tools on the Web can make the search easy, educate you about your options and help you save a lot of money on your drugs.

Here are some of the best resources:

• Consumer Reports Best Buy Drugs (crbestbuydrugs.org) is a tremendous resource for information about your medications, your alternatives and their costs. The drug reports include an easy-to-read review of the scientific evidence comparing drugs in a similar category (such as for high cholesterol or coronary-artery disease), including detailed descriptions of how the drugs work, in what circumstances various alternatives may help and the average monthly cost.

The drug reports and cost updates, which list average retail prices for every drug in the category, also highlight the CR Best Buy choices, which experts have identified as the best based on evidence of safety, effectiveness and cost.

• Rxaminer (rxaminer.com) is a great way to find generic alternatives, as well as other brand-name drugs in the same category that provide similar effect. Even if your drug doesn't have a generic version, you still can save a lot of money by switching to another brand-name drug (Rxaminer says the average annual saving per drug is $524).

Type in your drugs and dosages. Rxaminer creates a prescription drug pricing report, listing the retail and mail-order cost of that drug as well as generic and other alternatives. You'll also get other cost-saving strategies, such as pill splitting. The service is free, but you must register.

It shows, for example, that Lipitor 20 mg costs $114.11 for a 30-day retail and $342.32 for 90-day mail order supply, but the biggest savings could come from buying 40 mg tablets and splitting them in half - saving $714 in retail, $726 through mail service over the year. The report also shows that you could save more than $570 by switching to Altoprev, a different brand drug in the same category that typically provides a similar effect.

The report also lists several other drug alternatives, with information about cost savings and notes about differences. Before you do anything, you'll need to present the report to your doctor to find out whether it's safe for you to make the change.

The basic Rxaminer report is helpful if you're paying for the drugs yourself - if you don't have prescription drug coverage or if you're covering the costs yourself in a high-deductible plan. But the company also provides customized versions of the site to several large employers, insurance companies and prescription benefits managers, with details about the coverage and co-payments for each drug under the specific policy.

The company also provides another version of this service, PartDOptimizer, to Medicare beneficiaries with Part D prescription drug coverage at a few large plans, including AARP and Aetna, with company-specific reports showing the co-payments for the drugs and alternatives.

• After you've talked with your doctor about which version of the drug is best for you, then you can go to DestinationRx (destinationrx.com) and click on "Price Compare'' to find which pharmacy offers the best deal. The site lists prices for four of the biggest online pharmacies - including Wal-Mart, Drugstore.com, RxUS and Costco - and just added pricing information from more than 50,000 independent and chain pharmacies throughout the country. Type in your zip code, and you'll see the five pharmacies in your area with the best prices on your drug. The prices are updated weekly.