Thanks
Based on what you state - and assuming you want to stick with canon, I don't think the 7d is the right way to go. I stand by the Canon 60D recommendation.
Have a look at the first page chart -
http://www.dpreview.com/reviews/canoneos60D/
You won't need dual digic 4 processors if you aren't shooting real sports (not kids) or wildlife, nor the 19 af points - which as stated can have a steep learning curve dealing with expansion and tracking. The difference of 4% in pentaprism coverage is also a moot point imo. If you are shooting landscape, you are doing it from the screen on the rear, from a tripod, with the build in level. The screen is 100% view. 8.3 fps vs 5 fps? Hardly tangible for most - and a good fast card could make the difference anyway.
You will heavily benefit from configurable auto iso. You will benefit from the articulating screen.
Again, it's also in the super sweet spot for pricing. It's barely more than the t3i, but substantially less than the 7d. The difference between the 7d and 60d in price will get you either the sigma 30 prime, for low light and more limited depth of field - or will get you 2/3 of the way to a good zoom.
I think, as with computers, a lot of people want the best in photo gear. The 7d is is the crop flagship for canon - it's the best... but the few features it has over the 60d are not something most would use, outside pro sports or wildlife photographers.
My preference from canon is based on shooting prime lenses. If I was more of a zoom guy, I'd probably buy nikon, though their lens prices tend to be a bit higher.
The 60d will carry you for MANY years without the need for an upgrade, unless you chase better gear. It's a camera that you could really grow into...or it can be more simple. Since you state you know the basics of exposure - I'd say have at it.. and factor in the price of the magic lantern guide for another $12 or so!
Aperture and photoshop elements are completely different programs. They have mild overlap, but that's it. Lightroom and photoshop elements from the app store would be a great combo.
There are sales on lightroom regularly - it was just $150 on new egg.. and now can be had for $179 at other places.
As for MP - you have way more than enough with any of the current cams, even the 12mp ones.. unless you plan on printing billboards.
4 Grand is a GREAT budget. I could come up with a whole list I'd do with 4 grand.
I'd start with 60d (body only) $900
sigma 30 - great all around low light general view (nearly 50mm equiv) ~$550
canon 85 1.8 - get your portrait on $380
canon 15-85 - walk around lens $800?
That's only $2500 or so.. and you would be pretty well set unless you wanted something really wide for landscapes - at which point you could spend a bit more.
Sigma makes some decent lenses these days - you just have to figure out which ones they are, the 30 is great, and I also like the 17-50 as a walk around.. but recommend the canon for more range.
If you want glass to 'invest in' well - we can spend a lot more..
60d - body
canon 17-55 - I still feel the sigma is as good and half the price - also if you live in a dusty environment, this lens is prone to sucking it in.
35L (should be replaced soon, I'd wait for the next version)- expensive but WOW.
85/1.8
That's about 4 grand
Obviously everybody has different ideas about kit.. and it depends on what you want to shoot. I personally think starting with the kit I outlined first would be a 'smarter' choice... except the 35L and 17-55 can be resold for just about what they sell for new.. they don't depreciate more than 15% if kept in good condition.