Your choice of CAD system is much like everything else in life in that you get what you pay for.
If you want a no-frills, über-basic CAD package, I would consider DraftSight by Dassault Systems, which is free. It saves files in DWG format and you can add the symbols layer you want. Dimensioning and annotation are also a little on the crude side.
If, however, you want to work a bit smarter and develop tool palattes for your symbols, or use dynamic blocks, LT is streets ahead of DraftSight, but it carries the higher cost inherrent in more sophisticated CAD packages, which LT definitely is.
As far as I am aware, Autodesk no longer offers AutoSketch. You can find it on their website, but when you go to purchase online, AutoSketch disappears from the options available, which is a pretty clear indication it is a dead duck. (Please feel free to correct this statement anyone!!)
As both systems output DWG file, it ultimately, it comes down to what your primary requirement is, functionality or cost.
Having used both packages, I personally prefer LT as I think the additional functionality is worth the cost, just!
Umm you do realize you just answered an almost 5 year old post?
LOL!!
Thanks for the heads-up, I didn't realise that, but then at no point did I claim to be especially observant!!!
My only defence is that I have been a liitle over-eager to help a fellow member, but will definitely pay more attention to the discussion dates in future!!