"I'm too fond of it" means "I like it too much". There's not much difference between the two, but when you're "fond" of someone/something, it usually suggests that you've known the person or had that thing for a relatively long time, and that you've grown emotionally attached to it. Whereas "like" usually suggests your feelings towards someone/something are not as profound. For example, when a loving mother would say "I am fond of my children." instead of "I like my children." because "fond" suggests deeper feelings and "like" would make her sound too cold and detached from her children.

You can think of "like" and "fond of" the same way you can think of "xihuan" and "ai" in that they mean very similar things in different degrees. Though these are not extremes. Xihuan is more like fond, and ai is like "in love." I hope that wasn't too confusing. "I like this song." "I like her style." "I am fond of the way he looks at me." Being fond of something is the stage between like and love.

1. Yes, there is a difference. 'Too' means an excess , or more than is good or healthy. For example, you can say 'My problem is that I'm too fond of chocolate' . This means that you like chocolate such a lot that you eat too much of it, and that you are perhaps putting on weight as a result. 2. To 'be fond of' means to 'have an affection for'. With regard to a person, it is a feeling stronger than 'like' but not as strong as 'love'. You can also be fond of things. This suggests a very personal preference, which, as in the case of the chocolate example, may be excessive.