I've just received a ws-c3560g-48ps-s and noticed the lack of stack ports on the back, I thought all the 3560's were stackable, if so how the **** do you make it stackable? Guessing using the sfp.
The 3750 series switches are stackable, not the 3560 switches. You can as you say interconnect them using the SFP cable.
As Jon said the 3560's are not stackable . You will need a separate ip address to manage each switch . You can use gbic patch cables to tie them together thru ports 49-52 .
For layer 2 switches, only the 2960S and 2975 are stackable. 3750/3750E/3750X is the only model which support stacking.
Another method is to use Switch Clustering.
System Requirements to Implement Switch Clustering Technology
Configuring and Analyzing Clustering on Catalyst Fixed Configuration Switches