Got back from Italy this morning. I've made a detailed guide of travelling, costs, times, accommodation etc. This might come in handy for anyone wanting to plan a trip to the Italian Grand Prix.
Enjoy.
Not all of this information is applicable in every case. This guide follows how I did everything. Only use the information that is applicable to your case. The Milan>Monza stuff should be applicable to everyone. Obviously if someone was to use the same accommodation as I did, more is applicable.

Milan Travelling, Costs, Times
To
•Coach from Leicester to Gatwick T2 (£45)
•Flight from Gatwick to Malpensa T2 (£55)
•Bus from MXP T2 to T1 (Free)
•Train from MXP T1 to Bovisa (€11)
•Train from Bovisa to Affori (Included in above ticket)
•Accommodation (OstellOlinda - Website
From
•Accommodation (OstellOlinda - Website
•Train from Affori to Cadorna (€1)
•Train from Cadorna to MXP T1 (€11)
•Shuttle Bus from MXP T1 to T2 (White Bus, leaves every 15 minutes) (Free)
•Flight from MXP T2 to Gatwick (Return ticket)
•Coach from Gatwick T2 to Leicester (Return ticket)
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Out and about



Affori to Milan
•Train from Affori to Cadorna (€1) Leaves every 25 & 55
•Short walk
Or
•Metro from Cadorna to Duomo (€1) 3rd stop
Affori to Monza
•Train from Affori to Cadorna (€1)
•Metro from Cadorna to Stazione Centrale (Central Station) (€1) (Line 2, Green, 5th Stop)
(Following directions are applicable to anyone staying in Milan)
•Train from Stazione Centrale to Monza (End destination either Lecco or Tirano) (€3)
•Walk from Monza station to Autodromo (35-40 mins + 15 to track = 55 mins)
Or
•Shuttle Bus from Monza station to Autodromo (15-20 mins, plus 10-15 min walk to track)
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Notes
•Train from Stazione Centrale to Monza doesn't run at 9am. < 8am |•| 10am >
•Shuttle bus doesn't run on Thursday
•Shuttle Bus Leaves constantly from Autodromo and Monza Station (Friday>Sunday)
•15 minute walk from the Shuttle Bus destination to the Track itself.
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Collecting Race Tickets from F1.com (WWTE)
•Take your passport/Some other identification
•Take WWTE A4 Ticket sheet (Received trough email)
•Collection Booth, Vedano Entrance at the circuit
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Food & Drink
•One meal at track - Sandwich & Drink - €9
•Supermarket 3 minutes walk from accommodation - cheap. €25~ will get you plenty of food for the 4 track days, far more than at the track. Make your own sandwiches and take them with you.
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From Affori, total transport cost for F1 - Thursday > Sunday (1 Person)
•First Train - €8
•Metro - €8
•Second Train - €24
Total - €40
(If your staying in Milan, minus €8 for the First Train)
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Total Costs for 5 day holiday - Wed>Sun
•Accommodation - £100
•Coach - £45
•Race Ticket (General Admission) - £90
•Flights - £50
•Transport (Italy) - €40/£38
•Food & Drink - €15/£13 p/d = £65
Total - £383
(Only apply costs that are applicable to your situation)