The size of the avatar should be square, and 80x80 pixels or smaller. Check that, maybe? 
I found the link to your picture (clickie), but it doesn't show up under your name. There are a couple possibilities:
1) The image is larger (heigh & width) than allowed by the boards or
2) ImageShack doesn't allow direct linking to their pictures.
My guess is the second, since (I think) the boards will resize an avatar smaller if it's too big.
--edit--
Or, instead of linking to this address:
http://img300.imageshack.us/my.php?i...smabustzl8.jpg
Try this one instead:
http://img300.imageshack.us/img300/2...smabustzl8.jpg
Oh, that's why. Make sure you use the URL link, not the IMG one. Go to My Images, and copy/paste the URL link.
EDIT: And wow, that's good!
Awesome drawing!!
But yeah it needs to be 80x80.
I think you figured it out Sarrate, I posted the wrong link. Also meant to attach just the head. It looks bad though, I wonder why all of your little "heads" look nice and mine looks poopy. Ugh, sometime this stuff is too difficult. The head is 80 x 80...the bust is not.
I see, your current avatar is 56x80 when the size of avatars is 80x80. So, the boards are enlarging the width of it making it look grainy and disproportionate. Try this one, it should be a lot clearer. (Just upload to your own site, I can't gurantee that'll stay up forever and I wouldn't want your avatar going *poof* on you!)
Here, I edited the pic for you. See if you think it looks better.
http://img187.imageshack.us/my.php?i...l880x80gp1.jpg
EDIT: LOL I guess Sarrate and I were on the same lines...genius minds think alike and all that
Ok, I think it's fixed and posted correctly. I expected Photoshop to keep the 80 width when I switched to 80 height. Guess it did it differently. Thanks for helping out the girl who boarded the short bus without her helmet securely fastened ; ) PS - thanks for the drawing compliment as well. I like it but there are clearly some EXCELLENT artists on this board as well...Sorah's post comes to mind.
Karisma
1) cute name XD
2) I like your drawing. You have a better immediate understanding of lightsource than I was willing to look at when I started your chick's got nice form and 'form'.
3) And she's attractive. A rule I have had beat into me: "Never draw someone you wouldn't _ _ _ _." <_< I'm not kidding. LOL
EDIT: P.S. I'm not that good, trust me LOL I just know how to fake it really well! ROFL!
No seriously, if you have the brainpower and the knowhow, find some of my early stuff. *gags*
Click for Deviant Art Site - Commission List: OPEN
I must say, your avatar's quite nice... love the sweeping details of her hair =D
"Take the Yuan-Ti, bash them with a club made of frozen stupidity, then rip out their sense of subtlety with a rusty spoon, and then you have the Snakes of Mercy Isle" -Taltha Widowfang, drow stalker
Now playing at an MA near you: Dragonslayers #335375
There definitely is a lot of excellent artists here...why not join them? 
I really like your drawing style, your character looks great.
When changing sizes, look for a checkbox for maintaining aspect ratio.
Nice avatar, by the way.
Orc&Pie No.53230 There is an orc, and somehow, he got a pie. And you are hungry.
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Thank you all for the comments! To Sorah, I appreciate the compliment. If that's faking it, I'm even more impressed.
Ok, so I can be a bit of a goof, I drew my character and tried to post my head as my avatar, but somehow it seems to be getting blocked. Is it just me? If it is blocked does someone have advice on how to get my avatar to work? Sorry, I am not a master of the net by any stretch.