If your ip address is fixed maybe not if it isnt then it should change every reboot in theory.Its hard to block one indivdual IP address usually they block an entire IP range but that can block everyone not just the person they want to block.I cant see why they would block your IP address for just talking about other sites it sounds rather stupid to me.
Having said that if a site had blocked me for just talking about another site i would not even be bothered going back,petty sites like those IMO are not worth bothering about. Take your custom elsewhere there loss not yours.
In theory if you connect through a router you can log into the router control panel, change your mac address, and then disconnect/reconnect using your router control panel. Your isp will usually refresh your ip i am not 100% sure this would work as i have never done it. Or you could try somthing like this click here but it costs money.
You could maybe use a firewall to block your IP address from showing online,i know the old Sygate firewall pro had this feature for anonymous surfing not sure about the new ones.It could also block other sites from working as well so you have to balance the pro's and con's.