I had a follower with me when I got the housecarl. Selected follow me and she said I already had a follower (duh) and then she just walked off and disappeared. Where can I find her now? I've searched the city high and low and can't seem to track her down.

I lost her when I went on a quest with someone else, but she re-appeared in the hall where you first meet her, sitting at a table.

Try checking the hall that the Jarl stays in. If she's not there she might be in your house.

Yeah, that was the first place I looked. I'll keep looking back there. Thank you