How to use I2C between an ATtiny85 & ATmega328 ( TinyWire,or Wire ?)

I have a breadboarded ATtiny85 (currently 1Mhz until I get my 8 Mhz xtal & caps) and an ATmega328P-PU
with OPTIBOOT Bootloader running with a 16 Mhz xtal and loading sketches with FTDI BASIC .
Both are running sketches but the tiny loads from an UNO in Arduino as ISP mode.
The ultimate objective is a comprehensive data acquisition system.
I already have one DS18B20 running from an uno and displaying to an LCD.
I also have an Adafruit 31855 Thermocouple Breakout bd running from an UNO. I have a 3.3V/8Mhz
Pro-Mini breadboarded I want to incorporate eventually as well.
My problem is that I currently don’t know how to reconcile the I2C communication protocols in order
to get one or more ATtiny85s collecting data and sending it to a 328 because the I2C protocol I found
on the net is TinyWire and the I2C protocol I have used with the 328 for various circuits is Wire.
Additionally the 328 uses ONEWIRE for the DS18B20 and I don’t know if there is a “TinyOneWire”
because my understanding (limited as it is for someone who has only been doing this since Oct-31-2013
or just over a month, is that TinyWire is an I2C protocol , totally different from ONEWIRE and I don’t
know if the tiny can run ONEWIRE. So is there a way to collect data from ATtiny85s (temp, voltages etc.)
and have it report back to the 328 which interfaces with the outside world via LCDs (both 4-bit & I2C)
and also a SPI 6-DIGIT 7-SEGMENT LCD (which works but I need to study the example code more to
understand how to use it). Is there one protocol that works with both the tiny and the 328s or can
you mix and match one on the tiny and another on the 328s ? (yeah, it’s probably a dumb question…)
I have all the datasheets but I am a little confused because the code for analog pins on the 328 uses
the I/O designation "A0, A1, A2 etc but the tiny appears to use just (0), (1), (2) (3) etc… I haven’t seen
any use of the “A0” designation in any tiny code. I can’t find the section in the data sheet for the
328 that mentions this convention of using “A0”,“A1” etc. so that’s one thing I wanted to clear up.
I’m just looking for some links to tutorials or something to enlighten me. I mean the all circuits are
working in “standalone” mode if you will. I just don’t know if you can mix peanut butter with avacado
if you know what I mean…

raschemmel: I mean the all circuits are working in "standalone" mode if you will. I just don't know if you can mix peanut butter with avacado if you know what I mean...

I'm sure it can be done but unless you're forced to use a Tiny85 then it's probably much cheaper/easier just to get another Pro Mini. They're about $3.50 on eBay.

Ok. I'll change my plans and use one or more Pro-Minis to collect data and use the 16 Mhz ATmega328P-PU DIP with the OPTIBOOT Bootloader as my "core" processor. I've never done anything like this before so I have a lot of homework to do to learn how best to get them all working together with maximum Input (data acquisition) and maximum Output (data reporting/logging , ie SD card). Until I find an easier way to communicate I with the tinys I won't make any plans to use them for now.

Thanks for your suggestion. It makes more sense.