This has come up sooooo many times now.
People see the price of a grain mill and go.......... Oh dear, thats expensive. And no, there not cheap.
But years back before you could buy a grain mill easily on line (there was one or 2 american options available for the price of a small car), i tried cracking a Kg of Pilsner malt by hand, without a mill, for my first go at mashing malt for a partial.
Well.............. what a nightmare. I got there in the end but the memory of the work involved is well burnt into my head.
THis is back before i found AHB (it was probably just starting out like me) and me and a few others on here were on the old Grumpys forum. I asked the same question as you and got told the same, even searched the net and no luck, rolling pin, beer bottle as a rolling pin, coffee grinder, food pricessor, mincer etc etc.
I tried the rolling pin....... FAIL
I tried the food pricessor......... FAIL
So i wrapped it in a teatowl (ended up destroying 3 of them) and bashed it in handfull batches with a brick.
I got a lot of flour, a lot of whole grains that got missed and a lot of blisters and coins in the swear jar.
I then went and bought a Marga mill as it was just released as a Grain mill in Australia. It was slow but it did a good job.
I ended up building my own big mill, but not everyone can get on a laythe and turn down 10" long 2" dia rollers and make it adjustable etc. Its not cost effective to have it made and not everyone has access to the tools needed.
Sooooooooooooooooooooooo...................
THis leaves us with the array of comercially available mills on the market today. They will crack grain a LOT faster than a marga, do a great job giving you less huuk damage, improving efficiency, sparge performance (linked to efficiency) and all in all a more enjoyable brew day.
Once you spend the money you have it forever if you look after it, and the money you save from brewing your own will pay for it in well under the first year depending on how much you brew.......... the more you brew, the more you save
I recon your mad not to get a grain mill! Yes the HBS can do it for you but with your own mill you can set it up to crack the grain how you want it and to suit your mash setup and sparge style. You can also buy 25 kg bags which are a lot cheaper and this helps pay for the mill too.
I vote, even if you have to save $20 a week in a shoe box, GET A MILL!
cheers