Well, actualy I'm pretty good Solo. The thing is you have to be defensive, farm up your Siphon Strike, level up Spirit Fire, and Wither them to escape and it's quite easy to hold a lane against them.
But thats all you can really do, hold them back. You cant relly push that well with Solo Nasus, but his helth vamp is a big help. Just strike up the minions and with a health potion or two you rarely have to zap back to base...
But I;m just rambling now! XD