There are thousands, perhaps millions of different kinds of integrated circuits currently being manufactured that all have detailed datasheets. It's been a long time since the last time I used an IC that didn't have a detailed datasheet freely downloadable from the manufacturer's website.
It's been a long time since the last time I wanted to contact an IC manufacturer or distributor, and it didn't have a website with a "Contacts" page.
Many manufacturers give away free samples (a) (b) (c).
When I was a student, I got a few free samples from Motorola (now Freescale) and Cypress.
But most manufacturers don't have pricing information on their websites, because you and I can't buy anything from them. (By "you and I", I mean "people who buy less than a full reel of 1000 chips every week").
You and I buy from distributors and suppliers ( a b ).
The friendly people at these companies are happy to buy many reels of chips every week directly from the manufacturer, divide it up, and send onesies and twosies and a dozen here and a dozen there to people like you and me.
This is much faster than getting parts directly from the manufacturer.
To get pricing for the ICs and buy samples in ones or twos,
you go to a distributor's website.
Most suppliers these days have a freely-available web page for each IC with the various prices for that IC,
and a link to the original manufacturer's datasheet for that IC.
You don't even have to "sign up" or "log in" to get this information.
They make it easy for you to give them your credit card number and buy parts and pay for shipping right away.
Jameco, Mouser, Newark, Digikey, Omega, etc. have huge catalogs of parts and will typically send you a free catalog if you fill out the appropriate form on their web site,
although most people find it quicker to search on the web site than to read through a paper catalog.
Many medium-sized companies have a couple of "buyers", people whose full-time job is figuring out how to get all the stuff you need, and then once they're found one source, figuring out how to get it at lower cost -- perhaps from some other source, or perhaps by negotiating some sort of deal where the distributor gives us a lower price, and we promise to continue buying large quantities of that part from them for the next six fiscal quarters.
They use jargon like like "2% net 30" and "the next six fiscal quarters" that I don't understand.
Most manufacturers, distributors, and suppliers can't help you at all with your product.
They're experts on making and shipping ICs, not designing products using many ICs.
A few exceptional companies have helpful Field Application Engineers that do a lot of work talking and working with people like you and me, trying to make it easy for us to put their parts into your products.
You might find other helpful people at sites that list third-party design engineers.
(a) (b) (c)