I saw that under the info of the Toradora novel that the anime ends at volume 10, so I am assuming it covers all of the novel. Is this true or is there any sort of continuation from the anime?

Nope, not really, though the novel ending is sightly different from the anime... but not enough in my opinion to read from the beginning (though obviously a novel goes a little more in-depth with some areas, but that is to be expected)

Well, the content left out in the anime is big.
Tough I don't think it's necessary to read it, it isn't worth the time if you have already watched the anime.

Well what was different and how did it end slightly differently?

Don't worry. the content left out is not really important to the plot.
It's like the difference of saying:

• I went to the beach, bought a coke and while I was looking at the sea she came to talk to me
• She came talk with me while I was on te beach.

It's the same thing, just more detailed