Alright I've just found Sloan's Diary in the fifth spire and now it tells me to investigate in my journal and I have. I've looked through the entire fifth spire and nothing happened. So i then went to the guild and no-one had anything to say. So on hands and knees I ask for your help. Please tell me where to go next

I think you missed the point. You're supposed to open the diary. Some voiceacting will start (might have to turn up your volume), and your quest will pick up from there.

Oops i forgot to say that.
I read the diary but now I'm confused on what to do next...

Ok, Go into your Oblivion Journal and see if you have that quest update saying you need to talk to one named individual. Go to that one person. You should have a topic for conversation, it might even appear cryptic (meaning you might think the option doesn't apply). Make sure you go through every conversation topic, and allow the text to stay on-screen for a couple of seconds.

I think it's the maps & charts guy downstairs you have to talk to. He gives you the key to Rythor's office.

Oh-oh. Just remembered something. Liquidgraph has posted a brand-new update of Lost Spires (V14). It has full voiceacting now.

You can get it at: Lost Spires V14

Thank you for both the help and the link
That was all i needed ^^

You're welcome. Glad I could help.