As Edison notes, the 3560-E or 3750-E 24 copper port models are probably about the closest to you requirement for the edge switch, although note their two uplink port module slots can support either 1 10 gig port or dual SFP gig ports. I.e. they won't support both dual 10 gig and with 2 gig SFP but could support one 10 gig with 1 or 2 gig SFP. (BTW: there's also 48 copper port models with dual 10 gig module slots within the 3560-E and 3750-E, as well as the 4948-10GE.)
Another issue, is 10 gig on copper for 90 meters. Believe the 10 gig copper is only rated for 15 meters. Even with fiber, you need to be careful with the selection of the optics and fiber combination.
For a switch model that supports 16 10 gig ports, without using a 4500 or 6500 chassis, the new 4900M can without oversubscription, or up to 24 10 gig ports with some oversubscription. (The 10 gig port modules also support up to two gig SFPs.)
There's also a 3560-E that supports up to 12 10 gig ports but its forwarding performance is only 90 Mpps (wirespeed for about 30 Gbps, duplex).
As to comment on design, although I advocate gig to the desktop especially if the cabling plant can already handle it, since the overall volume of traffic doesn't generally increase, I've believe you can safely increase the ratio between the number of edge ports and to the uplink ports. So, for instance, instead of using 24 port models, with a single uplink, I think you can jump to a much, much higher ratio than the traditional 24:1. You might consider using 48 copper gig port models and/or stacking 3750-Es.
Second, I also sometimes advocate, gig (and sometimes copper, if possible) for backup for 10 gig, although sometimes in a dual channel configuration.
Third, although there are advantages to 10 gig links, when supporting "ordinary" desktops, even with gig connections, you might consider still using gig uplinks. With fiber, 10 gig is often less expensive than a large number of channeled fiber gig ports but if you can use ordinary copper gig ports, 8 copper port channels become an interesting alternative to 10 gig.
