You have probably heard about The Source which is now out in its third edition. You may have looked it up and discovered it run around $80. Despite its nearly 1,000 pages and nothing but rave reviews you thought was a little too pricey for your research.
That was an error in judgment. Oh yes, it is not inexpensive. But it is worth every penny.
The subtitle is "A Guidebook to American Genealogy" and that is precisely what it is. Think of it as a self paced course in American genealogy in one very thick and quite heavy volume. There are 20 detailed chapters. Take court records. There are 66 pages of detailed information as well as a comprehensive and up to date list of resources. That's because all the chapters are written by experts in that field of genealogy. If you concentrate on that chapter like there was a test you will become very knowledgable in court records. If you absorb all of the chapter on land records and then absorb Hone's Land and Property Research you will be an expert in land records. If you don't want to be an expert or even very knowledgable it is still the resource to have in your genealogy library.
Then there are the appendixes with all the extra information you might want about genealogical societies, historical societies, lineage societies, not to mention the National and State Archives.
Ok, your budget is really limited. Go online and search for a copy of the second edition. The price should be less than half. It won't be up to date but it will still provide you with a wealth of information that you can use in your genealogy research.