Hello mate,
Congrats on the new goals. I used to play Gods Own Game at representative level and I never found any real use for long or middle distance running(or I suspect jogging). I used to find, as Neil R suggests, for good CV fitness nothing beat shuttles or Fartlek training (google it) - as these will better reflect the stop/start nature of the game. The advice you're getting regarding becoming a member of a gym is also very sound and you should be able to get a decent program together.
Please don't forget that your club probably has training twice a week as well, this is essential to your development of your skills but also match fitness and also the ability to take a knock. Dependent upon the level of your club, and I am assuming you are not playing premier league, you will probably find that their training nights also feature a lot of drills and cardio work specific to rugby.
What position do you play? I could probably give some more specifc training advice if you play in the forwards, if you're a back then I can't help you with how to do your hair and look good on the wing
CMinOZ