Software To Slow Down Music For Mac

Transcription Resources. Software to slow down music. There are various other tools aimed at helping people to transcribe music from recordings. Here are the ones I am currently aware of. None of them are in head-on competition with Transcribe! As they all have differing approaches.
I have to second Jeremy: I'm equally enthusiastic about Transcribe. I've been using it for years, and it's still the best program I've ever used, of any kind: transparent in operation, almost no fat on it at all. (In earlier versions, there used to be none; recently they've introduced the odd bell or whistle which isn't strictly necessary or helpful. Not that they do any harm of course.) One extra Jeremy doesn't mention (and which I don't think any competitor program does) is it will slow down video too. BTW, slowing down more than 50% will affect quality depending on the quality of the original audio (not the slowdowner) - specifically the sample rate.
MP3s, eg, don't slow down as cleanly as WAVs. If you're working from CD tracks (rather than downloaded MP3s or youtube tracks, etc), Transcribe will record directly to WAV, which is recommended. But even with MP3s, I find Transcribe usable down to 25% (and occasionally more). It doesn't sound too good of course, but that's not the point: you can still hear what you need to hear. I tried Transcribe! And Amazing Slow Downer a few years ago, but did not purchase either one. Guitar Rig came with its own slow-down feature.
Later I got Wave Editor ($69) and it also has a very nice slow-down feature using Izotope. Twisted Wave (currently $39 bundled with 10 other applications) offers that feature using DIRAC.
Then there's the free Sonic Visualizer which can also slow down audio. I'm not sure if it can be applied to specific sections or only globally. Given the alternatives I thought that Transcribe! And Amazing Slow Downer were overpriced. I have not tried them recently so maybe they've added features to make them more attractive. I did like the software, btw. On the Mac there's also Capo and Neutrino.
Capo 2 only works in Snow Leopard. I have Amazing Slow Downer, it even has an iPhone app for 15 bucks that is pretty good. I have been using Transcribe lately and will probably buy that once I get a new computer because it is easier to navigate through the track. You can set markers which really help.
With ASD I always forget where the guitar solo starts and have to go searching. ASD doesn't save my spot when I exit the program so that causes some frustration. Both Transcribe and Amazing Slow Downer have free versions so try them out yourself. You can use the full version of Transcribe free for thirty days. The free version of ASD lets you slow down the first 2 tracks on a CD or the first 25% or so of a file on your computer. Both cost $50 which is really not bad considering how much music you can learn. You can't put a price on getting better as a musician!
I might just add that Audacity - a FREE multitrack audio editing and recording program - will also slow down without changing pitch, or vice versa. It's not as intuitive as Transcribe (because it's not dedicated to learning songs), and an action such as changing tempo needs a few seconds processing time. It's immediate on Transcribe. You can also place markers (as in the most useful aspect of Transcribe Neehan mentions), but again it's a slower more fiddly process. OTOH, Audacity is very easy to use for its main purpose: recording, editing and audio processing.

Word for mac change document settings. I own both programs, but I always use Transcribe for learning and transcription. If you really can't afford $50, I'd recommend Audacity, if only for all the other cool things you can do with it.
I might just add that Audacity - a FREE multitrack audio editing and recording program - will also slow down without changing pitch, or vice versa. When I compared Wave Editor, Twisted Wave, and Audacity a long time ago, Audacity was the worst sounding when it came to slowing down the tempo.
I just tried it again and although the sound seems better, it's still worse than the others and took much longer to process. I only reinstalled it a few days ago since it deals with ogg files, but it has a lot of room for improvement. I tried to upload the 4 files (original version, Audacity, Twisted Wave, and Wave Editor) but could not do it. Audacity sounds as though it's passing through a light flanger.