Let those authorities know, that laptop contains a) childporn b) highly confidential material about government etc... and voila, that laptop is being recovered in no time at all...
Not really. If you admit that your own laptop has illegal information (especially of that caliber) on it, they probably don't need the laptop as proof. Your own admission of guilt should be enough for them to arrest you.
Even if it doesn't, it's still illegal in most places to file a false police report. Most jurisdictions would consider any embroidery or embellishment of a stolen laptop report a falsification. In CT, filing trumped up charges can result in a fine - or even get you some 'slam time' if a judge gets really pissed off about it.
If you're insured, letting your insurance company know you have the whereabouts of your laptop and the police are refusing to get involved might get some action however.
The biggest problem the police have is getting a search warrant. Because it's possible to spoof IPs, some judges are reluctant to grant a warrant with nothing other than an unofficial source (i.e. you) providing the location. Cops also hate requesting a warrant unless they're extremely sure it will net something. Searching a place and coming up empty handed makes them look silly and exposes them to harassment complaints. Then there's also the problem with how much stolen merchandise is either acquired or handled by gangs. While most US police departments aren't adverse to showing the badge and drawing firearms when the situation warrants, risking a full scale confrontation over a $1000 laptop doesn't quite qualify as being worth the possible risk of life. And anytime the police engage in an arrest attempt there's always the potential for someone getting shot.
Frustrating as it can be (been there so I know), the sad fact is (barring extenuating circumstances) laptop theft is just too 'small potatoes' a crime for most police departments to get lathered up about.