Look at page 83 of the manual. Outlines what each function does. I would suggest you play and find the best for you. John Shaw's Photoshop CS3 Guide starts with bridge which is similar to LR. You can get that on line for $20. I just started on Shaw's training and find it very good.
Instead of using sharpening in the conversion I tend to sharpen selectively in Photoshop but I do know what the sliders do since I own LR. Since I dont apply any sharpening in the LR conversion process so I cant give you an hints on settings. I do know that LR sharpening is done to the luminance values only.
Amount : works as the name inplies and the same as the USM (unsharp mask) amount.
Radius: This applies targets effects to fine or more coarse detail.
Detail : This is too eliminate Halos
Masking : This masks the smooth lighter areas of the image.