Maybe I cannot use google well, but I couldn't find anything about this problem.

I have an album encoded in aac with Winamp CD Ripper. Winamp plays these files with no problems but in Foobar I can not seek and it does not read tags. However, foobar plays them.

Here is what winamp says about format of these files:
Format: AAC
MPEG-4 HE-AAC (implivitly signalled)
Sample rate: 44100
SBR: Present

Do I need any special plugin to play this kind of files or I just need to recode them?

And I also have problem with id3v2 tags in my mp3's. I used winamp before so I was changing only id3v2 where needed but not id3v1. Now in foobar it ignores my id3v2 for some reason, taking some info from id3v1 and some from id3v2. I've seen this kind of problem on some forums but they were talking about changing preferences in Playback-Inputs. In my foobar there is noyhing in there.

And the last question is about freedb tagger. Is it the same as Gracenote tagger in Winamp? If yes then how can I find info about one single song? If not, then where can i find a plugin similar to winamp's one?

Thanks in advance.

I know you may hope a quick solution.However, some articles are helpful.
Link: Foobar2000 Manual - Tags2

Are those aac files embedded within an mp4 container or is it just plain raw aac?

It is plain aac. Now I see the problem, I tried to put it into mp4 container and it worked, but winamp tags still weren't copied. Thanks for the reply.

OK. So what about id3v2 and freedb tagger?

FB2K merges the content of all tag types found in the file. In case the same item is present in both fb2k will use the longer string present.

About freedb and Gracenote: No they are not the same. They both are two different providers for a very similar task. Gracenote is proprietry whereas freeDB is open. It is not possible to look up tag info for a single song with FB2K in freeDB with it's current implementation.

Why it doesn't give priority to id3v2? Nevermind, I just changed tags for songs that didn't work.

OK, I have one more question, I don't think it's so large to open a new thread: how to check in playlist if item is in playback queue. Plugins can just show another window with items in a queue, but i just want to know in my playlist whether the item is queued. Can I do this with foobar? Is there something like %is_in_queue%?

EDITED: Oh, sorry, I've just found that it is impossible.

You should check the Encoding format setting in Winamp. It should be set to MP4/aacPlus (or one of the other ones that start with MP4/) instead of aacPlus.