I haven't over sharpened my photo — it looks great in Lightroom and Photoshop CS5, but when I upload it to my webpage, it has horrible ghosts/halos around much of the subjects. I have tried it with two different color spaces: sRGB and A98, but both give terrible ghosting and look flat.
It doesn't solely depend on the source image quality when you're uploading your photo to a website. The website does some sampling, even may convert the image to some other format for better web usability. I am not sure which service you're using for your website or if it is a custom development or not.
For example, flickr, 500px etc handles photos way better than facebook does. No matter how good quality picture you upload, they will apply their own predefined modifications to it.
First, for the web only use sRGB, this is the only color space supported by all the major browsers (meaning that if you use another color space than either some visitors will see wrong colors or the web site's software will "helpfully" convert it to sRGB for you).
Now, about the sharpening - most of the picture sharing web sites (and some gallery software for sites you operate) will modify your picture, they re-compress it so the file is smaller and often downsize it to a smaller resolutions, those reduce the image quality and make it a little softer so they also sharpen it.
So, your options are:
- Turn off sharpening in the web site's software (if you have control over it)
- Switch to another site/software that doesn't mess with your images (if you don't have control)
- Don't sharpen (or significantly under-sharpen) in Lightroom so that the picture looks good after the site's sharpening (if you can't switch site/software)