For the background : I am working in IT Consulting in France in a "permanent" contract, and have read several contracts in the field. I'll answer the three clauses you mentioned separately. About the 10-page : my contract was 8 or 9, iirc, so it doesn't strike me as too much.
Short story long : if you feel something is shady, consult a lawyer.
1. It says that I can't recruit to the company's clients for 12 months if I terminate the agreement[...]
I have the same agreement in my contract. This is a pretty standard clause if you are doing some kind of consulting work.
A classic case is the following : you get formed by your company, you get your first big mission for the client, client likes your work, and makes you an offer, which is generally more appealing than your current situation. He wins, because he will pay cheaper than contractual work - and you win. However, the company that previously employed you spent money on recruiting and forming you - they are protecting themselves from that.
However, it is also classic to have one of the following in the clause :
Upon mutual agreement, this clause is suspended.
If you leave and the clause is not suspended, the company will pay to make up for the constraints on your job search (5-20% of a year's income depending on the companies)
2. It also says that I'll have to pay 50k$ if I break something important from the agreement[...]
This one looks shady. If you accept this clause, it must not be open to interpretation. There has to be a clear list, so that you don't break something important by mistake. You should consult with a lawyer on this one.
That being said, even without that clause, I would refrain from installing illegal software on my profesional computer...
3. It also contains 3 months notice after 3 months of working there, which is a lot.
Depending on your country, this could be standard. A significant part of permanent contracts in France ask you for 3-month notice, once your trial period is completed.
Upon mutual agreement, this clause can often be suspended. Watch out for the wording - while 3 month is classic, it can often be reduced if the company has a suitable replacement and if you have transfered all your activities.