1. Use an analog switch chip(s)/analog multipexer chip(s). For example, the MAX4617 an 8:1 analog switch.http://www.maxim-ic.com/datasheet/index.mvp/id/2064
2. Yes, use an ADC(s) with I2C or SPI interfaces. An example would be this chip MCP3208http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en010534
12-bit ADC, octal part, SPI interface. Connect up as many as you need, common SCK/MOSI/MISO connections, need a unique slave seelct per device.
I have one on a board now, got some basic code written, will be testing soon.
3. Have you looked in the Playground section yet? I bet you will find an example there.