if you're looking for traffic under 100mbit, you can find the foundry load balancer switch on ebay for fairly cheap. the foundry serveriron XL FCSLB ( 8 or 16 ) the 8 or 16 mean how many ports there are. The setup is not that bad. the serveriron comes with a small gui you can use to configure the load balancer.
If you're looking for free opensource stuff, check out the already mentioned items above and this place
http://www.ultramonkey.org/
uses LVS and HA
Good luck