The lab notes aren't the giant smoking gun some of you are making out. The guy was a chemist, he had books of lab notes, notes that are gibberish to 99.9999999% of the police out there.
The notes won't have names of people.
The notes won't have locations.
It doesn't have Walt's formula, it has an analysis of the product.
It probably does have Gus's formula, which will be pretty useless since there won't be any Gus product from here on out.
All it will really do is highlight a particular motive for killing the guy and that is even if the cops pick up on it. Do you really need a book of lab notes to think that the shooting of a chemist might be drug-related?
As far as his cellphone goes, all those numbers will lead to burners.