Thanks for sharing the Google Sheet.

I've added these functions to get data from Bitstamp and Bitfinex. Call them from the cells as you would ccprice (including the last parameter which references the cell I5 that gets updated with the timestamp upon refresh)

function bitfinexPrice(name, datetime)
{

var response = UrlFetchApp.fetch(url);
var json = response.getContentText();
var data = JSON.parse(json);
var price = data["last_price"];
SpreadsheetApp.flush();
return price;
} var url = "https://api.bitfinex.com/v1/pubticker/" + name;

function bitstampPrice(name, datetime)
{

var response = UrlFetchApp.fetch(url);
var json = response.getContentText();
var data = JSON.parse(json);
var price = data["last"];
SpreadsheetApp.flush();
return price;
} var url = "https://www.bitstamp.net/api/v2/ticker/" + name + "/";