The advice of an 8" dob is spot on,except if you aren't planning to move it much and aren't limited too much by budget, it might be worth looking at something bigger (8" good, 10" better, 12" ...). (although I hear you say $300). I'd also agree that Bintel or Andrews are the way to go.
One cautionary note: I don't know if you've had much experience looking through an astronomical telescope, but many people seem to be unaware that even with a large scope
you will not see what is shown in astro images. You will be able to see many deep sky objects, but they will not show colour, as your eye will be using it's night vision rod cells, which only show things in shades of grey. If you're ready for this and take some time, you will be amazed at what you can see in a dark sky nebulae, globular and open clusters, galaxies , but its not like the pictures. And for planets, an 8" scope will show good detail + colour on Jupiter and the rings of saturn the moons of both and tranist etc, but you will still be limited by atmosphere to <300 magnification. You will see lots, but the planets won't seem huge. I only say this because a lot of people seem to get very disappointed with their first scopes if they are expecting colourful nebulae/galaxies and planets looking as big as the moon etc. This forum is littered with threads "what is wrong with my telescope" etc.
It might well be worth going to a star night with the Canberra (
http://www.mso.anu.edu.au/cas/ ) or MacArthur (
http://www.macastro.org.au/home/ ) astro societies. You will get a good idea of what telescopes are what and what you might expect.
If your expectations are realistic, this can be the most absorbing and addictive exploration.