Anyone know if there's a possible way to stop these attacks?
If you're being targetted for an attack, and you want to stop it(during attack) can you somehow stop it from preceeding its attack?
http://www.cert.org/ (http://www.cert.org/)
More specifically http://www.cert.org/archive/pdf/Managing_DoS.pdf (http://www.cert.org/archive/pdf/Managing_DoS.pdf)
If your problem is resource use on your network connection; the amount of packets coming in flooding your connection; then no, not unless other people help you.
If your problems is resource use on the server; some application running out of sockets, handles or similar; then yes - somewhat. Look into enabling syn cookies which will significantly reduce the resources required on the server to handle a syn.
For the latter case, if the attacker uses a fixed source IP or some similar pattern, you could also block it with a local firewall, ipsec, or similar.