Since you've made no effort whatsoever to do a
tiny bit of research, I reserve the right to sound grumpy/disrespectful.
Seriously dude, how difficult can it be to cast your eye over the rest of the forums? Generally speaking, packages don't come with any strings attached to artwork created by the user. What usually happens is that they either say give them a little mention, or charge you a fortune for the package.
Since you're working on a budget, I'll suggest two freebies:
Wings3D : Free 3D modeller (by far the
best free modeller)
DeleD : Free level editor (never used it... so I can't comment - could be good after U6 starts supporting multitexturing)
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