I was recently looking for aofroobs’ downloadable skill chart by Arenas and had to dig into archive.org to find it.
Since I think this is still a useful resource, I’ll repost it here 
Download link: Anarchy Online Skill Chart.
The chart shows the IP cost for every skill for every profession. This can be useful for deciding what weapons to use or to plan a twink.
On a level 200 character, the skill colours mean:
- Green skills (1-1.4) can be raised to 600
- Light blue skills(1.5-2.4) can be raised to 540
- Blue skills (2.5-3.4) can be to 480
- Dark blue skills(3.5-4.4) can be raised to 420
- Very dark blue(4.5-5) skills can be raised to 360
Base abilities modify this. For example on a solitus with maxed abilities this would mean:
- Green skills (1-1.4) can be raised to ~720
- Light blue skills(1.5-2.4) can be raised to ~660
- Blue skills (2.5-3.4) can be to ~600
- Dark blue skills(3.5-4.4) can be raised to ~540
- Very dark blue(4.5-5) skills can be raised to ~480
More elaborate details and a similar chart can be found on aodb.us.