What are some sources for lists of chemical formulas?

Endmemo, About.com and Convertunits.com all have lists of chemical formulas. Chemistry for Kids also has a list of chemical formulas on its website as well as a simple explanation of how to name chemical formulas.

The chemistry section of Endmemo has a compound name formula search that returns the formula, name and molar mass of a chemical compound. The list at About.com provides users with a visual representation of the chemical compound as well as its name and formula. The list on this site is not searchable, but it is split into organic and nonorganic compounds. Each entry in the Convert Units list gives information about the mass percent and atomic mass of each element in that chemical compound.