Heres to connecting info for Gamecube or GBA (Pokemon)
R/S to Emarald :Game Link Cable
R/S to FR/LG :Game Link Cable and need to get the ruby and sapphire from Celio
R/S to R/S :Game Link Cable
FR/LG to Emarald :Wireless Adapter / Game Link Cable
FR/LG to FR/LG :Wireless Adapter / Game Link Cable
Emarald to Emarald: Wireless Adapter / Game Link Cable
Berry Crush: Wireless Adapter
Union Room: Wireless Adapter
R/S to Pokemon Stadium (Gamecube)Gamecube to GBA Connector Cable
FR/LG to Pokemon Collesuim: Gamecube to GBA Connector Cable
Emarald to Pokemon Collesium Gamecube to GBA Connector Cable
Stumbed across this old site xD