HMRC - https://www.gov.uk/government/organisations/hm-revenue-customs
Companies House - http://www.companieshouse.gov.uk/
HMRC Self-Assessment payment options - https://www.gov.uk/pay-self-assessment-tax-bill
HMRC Corporation Tax payment options - https://www.gov.uk/pay-corporation-tax
HMRC VAT payment options - https://www.gov.uk/pay-vat