Yo Carlos! Here's a thread where I have been laying out some options in inexpensive audio interfaces:
https://homerecording.com/bbs/showthread.php?t=283098
That said, there are some things to consider. First of all, for what it does, the H4 is a pretty good machine. People will advise you against it, because of the advantages of using the computer you already have to record music. In the long run, the computer has more processing power than a handheld field recorder. If you get serious about all of this, you'll end up using a computer, with other equipment, as the centerpiece of your recording rig.
I am on the other side of the discussion, and here's why- I started recording on a KORG PXR4 Pandora, another micro recorder, which I still own, and still use. I cut my teeth, as they say, on that little bugger, and although I now own a fairly respectable project studio, I still own the Pandora, and I still use it (until about a week ago). Why? It is a notepad or sketchbook for a recording artist. It goes where I go, in my guitar case. I have used it as a remote recorder, for interviews, for recording ideas, as a preamp for a talkback mic, as a reverb unit when the reverb in an entire band's PA died during a gig, etc. When you move on, and you will, if you stick with recording, the little remote unit will still find uses.
I would also advise against USB mics, because they have such limited uses. For that application, I prefer this:
http://www.8thstreet.com/product.asp?ProductCode=44712&Category=Audio_Interfaces
That way, at least, you can have a real mic that you can turn into a USB mic when you need one. It's not a bad option if you use a laptop for a sketchbook.
In the end, there are countless options. I think the best bang for the buck is a USB enabled audio interface, as discussed in the thread above, and a good cheap mic, such as Sennheiser e835. But I would also argue that a good micro recorder is a very handy thing, much more useful than most people on this board think. The H4 also has the huge advantage that it can be used as a USB enabled audio interface, and you can plug any mic you want into it. Is it a great mic preamp? No. But then, neither are the preamps in other cheap interfaces, or in a USB mic. Quite a few people, I bet, will disagree with me on this, but I think the
Zoom H4 is a very good place to start recording, and a pretty versatile piece of gear. On the one hand, it can travel with you as a mobile recorder and sketchpad. At home, you can jack a mic into it, and send the signal straight to your computer for further processing. Combined with a free software program like Audacity, you could do a lot more in the studio with an H4 than most people presume.-Richie
BTW- after using the Pandora for about 6 years, I just upgraded it to an H4, not because it ever failed me, but because it is obsolete.