Guys i think the whole concept of looking for someone from the future making search engine inquiries in our time is just wrong... reason is because they won't need to since they will have what they need already. There are many methods to do this and the time traveler can actually prepare the internet for such things without us knowing it. At least if I were one I would take measures such as these:
Use existing infrastructure to do it:
1. I came across a site the keeps sort of backups of sites. You can view what a site looked like as far back as the 90's. I have forgotten what the address is, but i am sure if yu google it you will find it. 50 years from now you can just refer to it even if the internet is dead or carry it around and browse it as you browse the net now and index it for searches.
2. Besides, Google and other search engines do backups of their indexes. So these backups can be used to do a search on a specific period by a time traveller. TT can just pack it on some super nano computer memory, enough to keep 15 decades or more of indexes and do searches offline.
Use own future-tech to make his presence stealthy:
3. Look, the dude can actually just carry nothing but his super nano pc with some saved searches, use some system he sets up NOW (PAST) to send (save) a message that another computer intercepts 50 years from now and then save the search results on memory that he will carry around to the past as he travels in time. Whatever inquiry he does on his system in the past, will automatically be saved on his system now then refered to by a computer in the future then saved to a memory module that he will later carry with him on his portable super pc that he carries to the past.
4. Make a crawler or his own google that save the index to the future. (What if Google is just that pretending to help us, but instead a secret future link of info?) If they can send a human back here, i bet it will be very simple to send info to and fro future real time. Sort of making a call to the future. So TT will have a self dependent system on our internet.
BONUS to TT: Should anything change, then it automatically ripples into the future and comes back with him the moment he time travel back to the past. LOL note (he just travels once and whatever changes happen NOW in the timeline, it changes in the DB and the NEW info is instantly available) what's intresting is he'll never know something changed.
Sorry folks, I don't see why anyone should google on slow primitive machines to find information they may have already.
just be imaginative and u will see what i mean. Don't expect computers, security, algorithms, search engines, etc to be as primitive as they are now in 10years, whatmore of a society that can make a time machine and use it to displace a human successfully.
We are under priviledged if a TT exists folks