If you are talking about converter lenses (telephoto and wide angle), there are a few that will fit the Olympus C-770.
http://raynox.co.jp/english/digital/c750uz/index.htm
You will have to use the Raynox adapter tube instead of the Olympus CLA-4 tube.
There are probable others, but I could not find them.
Interestingly, the Olympus TCON-17 and WCON-07 lenses are very popular and adapted to other brand of cameras.
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Can I place any lens on my Olympus C-770 with an adapter or can I only use the ones at the olympus website?

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