Sounds like you want the WS-C3750G-24TS-S or the WS-C3750G-24TS-E. It has 24 ports of 10/100/1000 copper, and 4 small form-factor pluggable (SFP) uplinks. You have to decide whether you want just the SMI software (static and RIP IP routing) or the EMI software (full-featured IP unicast and multicast routing).
Also, get the GLC-LH-SM for that single-mode fiber interface for the 3750G. Good to 10km (6.2miles); maybe even further, if your SMF was installed well.
At present, there are four distinct types of hardware in this product family. Two have copper ports that are 10/100 only, so you don't want them. And the other two have 10/100/1000 copper, but one of those doesn't have SFP uplinks at all. So you want the one that's left, which I listed at the beginning of this post.
No unusual configuration needed between the 3750G and the 6509 to setup VLAN trunk ports. The 3750G will support ISL or 802.1Q, as does the 6509.
Hope this helps.
