This depends on what functionality and overhead you require/desire but I would suggest using:-
Layer 2 (Edge Ports)
You might want to look at the following for your edge connections:-
3CR17561-91 4500-26 Port
3CR17562-91 4500-50 Port
3CR17571-91 4500-26 Port with POE
3CR17572-91 4500-50 Port with POE
3CSFP91 1000Base-SX SFP Transceiver (Short Range Distances)
3CSFP92 1000Base-LX SFP Transceiver (Long Range Distances)
If you think you need more powerful switches and you can stamp up the cash, then:-
3CR17250-91 5500G-EI 24 Port
3CR17251-91 5500G-EI 48 Port
3CR17252-91 5500G-EI 24 Port with POE
3CR17253-91 5500G-EI 48 Port with POE
3CSFP91 1000Base-SX SFP Transceiver (Short Range Distances)
3CSFP92 1000Base-LX SFP Transceiver (Long Range Distances)
Layer 3 (Aggregation/Distribution Switches)
You might want to look at the following for your edge connections:-
3CR17258-91 5500G-EI SFP (Please note empty SFP slots)
3CSFP91 1000Base-SX SFP Transceiver (Short Range Distances)
3CSFP92 1000Base-LX SFP Transceiver (Long Range Distances)
Cables
All the SFP transceivers use an LC connector on them so make sure you use the right cables.
Hope this helps mate.