Newbie question. To get into 3d printing, do I need to plan on building my own?
No, but you will pay a premium to get an assembled one. Building one is really a good way to get familiar with how it works. I think many people do not struggle so much with the assembly as they do with getting everything level/in tram and then learning how software/firmware settings affect your machine and the quality of prints. This should not discourage you as this information is discussed very frequently and there are many good guides to get you going.
Edit: Most printers will have to be leveled/trammed at some point no matter if you assembled it or it was preassembled.
I own a printrbot, built it myself (several times as there were no directions at beginning) Still not working. Long story, many issues, yes I have used the forum and no I am not stupid. Frustrated…oh yea.
Waiting on built and calibrated Rigidbot. Worth the additional 100 bucks for a working printer. Until then using shapeways.
There is always the staples 3D printer… only 1200$
Many people go with DIY assembly, but Solidoodle is a good option for a low cost system that works out of the box : $599 with a heated bed for printing both ABS and PLA plastics or $499 for PLA-only printing (no heated bed). I received mine in less than a week and have been happy with the print quality.
Some of the older RepRaps were real headaches to build, but if you do your homework, a Prusa i3 is pretty simple…
The biggest assembly problem I could see happening is not putting on the x and y idlers, unless you actually break the plastic parts
But, like others have said, there are numerous fully assembled models for decent prices, such as the printrbot family (printrbot simple starts at $299 or a solidoodle…
Another thing you can do to save yourself some of the headache is to get a RepRapPro kit…
But those are all Mendel’s and a Huxley, which means complicated assembly and fiddly calibration…
have a look at makibox
you can buy a used/built one from more adventurous people: some of us will end up building more printers than we can use 
Assembled is THE future and our future. The Printrbot Simple is $299 as a kit and $399 assembled. The Jr v2 will be $599 assembled. The Plus is $999 assembled. You decide if those prices are a premium or smart money. We think it is smart money.
Ps: to the Printrbot owner having trouble, we will go to any length to get you printing! Contact us!
Brook
CEO/founder
Which printer is better Prusa Mendel i2 or Prusa Mendel i3?
Prusa i3 is much simpler to build, but there’s not as much documentation. The i3 is also easier to get level amd calibrated, because its structure is square instead of triangular. Also, many people who used the i2 have had problems with side to side wobble, and the hanging z axis falling. I’vheard of people who have had the z axis slip out of the coupler amd crash mid print.
What about bukobot or delta printer?
BukoBot just put out a new version, not well documented (yet).
Delta printers are fine, and probably simplest to build, but there aren’t any build guides (you really don’t need any).