LexisNexis, a premier research tool, now has a low-cost option for people who need only occasional searches. It permits users to buy selected documents individually without paying a monthly fee.

The company says the new service, at http://AlaCarte.LexisNexis.com, provides access to more than 3.8 billion documents.

Users can search over 20,000 sources of news, public records and government information, including top newspapers, magazines, and transcripts, company and industry reports, deed records, liens, state and federal laws and intellectual property. The information goes as far back as 1968.

Searches are free; access to documents costs from $3 to $10 each.

In addition to a simple keyword search, the advanced search page makes it easy to search for articles about an individual or company, to select a range of dates, or to narrow your search in a number of other ways.

If Google or another free search engine doesn’t turn up the information you need, or returns thousands of mostly irrelevant hits, LexisNexis AlaCarte is an inexpensive way to zero in on exactly what you’re looking for.