The Supreme Court: Empowerment & Systems

Why are some cases not heard by the Supreme Court? 

The Supreme Court has no police force and a relatively small budget, so where does it get it's power?

How does it enforce decisions? What does this quoatation mean, "Judges are just making too much legislation"? 

From what I understand, judges make decisions regarding legislation, mostly based on precedents from other cases. So what actually happens? It seems to me that judges are as politicized as politicians. But judges are not politicians???