I don't know what you mean by 'using all the sound library'... I assume you mean using only Logic's built-in instruments and effects?
It depends on the type of music you are making. There are some very good third party instruments and effects available. Many of these are used by Pro Studios. Other Pro Studio use these and a combination of hardware too.
However, the plugins and sounds in Logic are very very good... and it's possible to get close to the Studio sound. So it depends on how you use them and the quality of your mixing and mastering skills.
Even though you can Master in Logic, a Pro Mastering engineer withe good experience, a good ear and equipment and a sound treated room is priceless.
Yes! There are two really good mixing tutorials available specifically for Logic:
If you want to create your own bundle, it sounds like you may be interested in the 5x 400 range of Logic tutorials.
Hope that helps,