As already mentioned, some of the converters are rubbish but there are a few worthy of consideration. The link discusses some of the better options, specifically to fit a Lumix FZ30 but clearly can fit other cameras as well.
http://www.cs.mtu.edu/~shene/DigiCam/User-Guide/FZ-30/Converters/Lenses/WideAngle.html
I actually own the Olympus WCON 8B which is beautifully made, has a 62mm thread fitting, but is very heavy and partially obscures a built in flash. Step down rings might be needed for a lens with a smaller filter fit size. I bought mine on Ebay for £25 and it appeared to have never been used, new these were about £180. Prices asked vary enormously, but they do sell at sensible prices for bid items given some patience. There are similarly high quality Telecon (TCON) and Macro (MCON) converters from Olympus prior to the cheap feeling and plastic current Pen add-ons, but a lot of different models which aren't always correctly described. Examples are the TCON 14B, MCON 35 and MCON 40. Lastly, there is an Olympus WCON 07 (not the 07C) which has a 55mm thread fitting , wider but sacrifices image quality compared to the 08B
The WCON 8B will reduce the focal length by a factor of 0.8. Your widest lens setting would appear to be 17mm, so this would reduce to 13.6mm equivalent before (any) Crop Factor is applied. In addition, if the front element of lens to which the converter is fitted rotates or extends with AF, the weight of the converter would place a huge strain on the AF motors, so it would be MF only. Some image distortion will be added as well. If 13.6mm is wide enough, then this could be a cheap solution, if not, then an actual wide angle lens will need deep pockets, even secondhand. In the end, I bought a Nikon Fit Tamron 10-24mm crop sensor lens.
A summary of Olympus Converters is here:
https://ohse.de/uwe/articles/oly-converters.html#wcon_07