I’ve found the International Genealogical Index (IGI) available at FamilysSearch.org very useful in the past. It has been a mix of community indexed sources and community contributed records. Apparently this mix meant that the records weren’t equally reliable. The problem is in the process of being resolved with the creation of two separate collections searchable from the IGI collection page. If you click on the link now you’ll find that the IGI collection page isn’t available yet— I’ve bookmarked the page and will keep checking.
The Community Indexed IGI is a database of sources that were indexed by the genealogical community volunteers from Church and vital records. Each record is organized into their specific collections, such as Birth, Marriages and Christenings 1538-1935.
The Community Contributed IGI, as the name “contributed” suggests, is a collection of personal family information given by individuals to the LDS church. Many of these records illustrate the point of view of the donator so the quality of information is not precise. There are duplicate entries, secondary sources and inconsistent information but, nevertheless, useful enough to provide a search feature.
If you’d like search the IGI click on FamilySearch.org and search using the form on the main page.
“It is best to enter a little information at a time. Entering too much information may return few matching results, as the search engine will look for only the records that include all the information you entered. No records will include all events, places, parents, and spouse. For example, a marriage record will have a spouse and a marriage date and place; a birth record will not have a spouse but will have a birth date and parents.”